Device for electrophysiological recording from the eye

ABSTRACT

The present disclosure provides electroretinography devices configured to detect biopotential signals from an eye of a subject. In some embodiments, the device is configured to prevent the subject&#39;s eyelids from closing over the device when placed in contact with the anterior surface of the subject&#39;s eye. In some embodiments, the device has a Young&#39;s modulus of no more than about 50 MPa. In some embodiments, the device includes a diffusing or refracting element configured to scatter, focus or diverge incident light. In other embodiments, the device includes a void through which incident light can enter the subject&#39;s eye without passing through any portion of the device.

CROSS-REFERENCE TO RELATED APPLICATION(S)

The present application is a divisional application of U.S. patentapplication Ser. No. 17/188,130 filed Mar. 1, 2023, which is acontinuation of U.S. patent application Ser. No. 16/132,257 filed Sep.14, 2018, which is a continuation of U.S. patent application Ser. No.15/407,450 filed Jan. 17, 2017, which is a continuation of U.S. patentapplication Ser. No. 14/338,640 filed on Jul. 23, 2014, which claimspriority to U.S. Provisional Patent Application Ser. No. 61/857,674,filed on Jul. 23, 2013, the disclosures of which are incorporated hereinby reference in their entireties.

BACKGROUND

The retina is the thin sheet of neural tissue that lines the inside ofthe eye, and which is responsible for converting the light that entersthe eye into visual information that is then passed to the brain in theform of nerve impulses. Electroretinography (ERG) is the process ofrecording the bioelectric response of the retina in response to a visualstimulus, such as a brief flash of light. The response that is recordedwhen performing electroretinography is a voltage versus time waveformthat can be analyzed to reveal a great deal of information about thephysiology and health of the retina. ERG recording is therefore acommonly employed technique in vision science and ophthalmology. Forinstance, in ophthalmology, ERG recording can be used to diagnose adisease that affects the retina, such as glaucoma, or to monitor theeffects of a treatment strategy aimed at a halting or reversing thedamage caused by a retinal disease. ERG recording is non-invasive and isroutinely performed in human subjects and animals such as mice, rats andcats.

ERG recording is accomplished by placing a recording electrode in gentlecontact with the cornea, and then presenting a visual stimulus to thesubject. The recording electrode can take one of several differentforms.

Current reusable electroretinography devices can be expensive, scarce inthe market, difficult to clean for reuse, uncomfortable for the subject,difficult to insert on the eye, and pose a risk of corneal abrasion dueto the stiff materials used for construction. Current disposableelectroretinography devices are typically highly unstable on the eye andproduce inconsistent signals. Improved electroretinography devices areneeded.

SUMMARY

The present disclosure provides electroretinography devices having thestability of a reusable device with the convenience of a disposabledevice formed primarily from a flexible, non-abrasive material toenhance subject comfort and safety. In some embodiments, theelectroretinography device includes an electrode configured to contactthe surface of a subject's eye. In some embodiments, a method ofrecording electroretinographic data includes contacting the surface of asubject's eye with an electrode housed in an electroretinography devicedisclosed herein.

In some embodiments, the present disclosure provides anelectroretinography device comprising an ocular portion configured todetect a biopotential signal from an eye of a subject, the ocularportion including a proximal portion configured to be placed in contactwith an anterior surface of the eye, a distal portion including at leastone side wall, and a conductive element housed in the ocular portion;and a signal relay operatively connected to the conductive element andconfigured to transmit the biopotential signal from the conductiveelement to a signal processor.

Additional embodiments of the present technology may comprise thecombination of one or more of the features described above, as well asvariations of each feature that will be apparent to those of ordinaryskill in the art based on the descriptions and figures included herein.

BRIEF DESCRIPTION OF THE DRAWINGS

Many aspects of the present technology can be better understood withreference to the following drawings. The relative dimensions in thedrawings may be to scale with respect to some embodiments. With respectto other embodiments, the drawings may not be to scale. For ease ofreference, throughout this disclosure identical reference numbers may beused to identify identical or at least generally similar or analogouscomponents or features.

FIG. 1A is a perspective view of an electroretinography deviceconfigured according to one embodiment of the present technology.

FIG. 1B is a perspective view of a portion of an electroretinographydevice configured according to another embodiment of the presenttechnology as viewed from the proximal side.

FIG. 2 is a cross sectional view through one embodiment of anelectroretinography device configured in accordance with the presenttechnology.

FIG. 3 is a cross sectional view through another embodiment of anelectroretinography device configured in accordance with the presenttechnology.

FIG. 4 is a cross sectional view through another embodiment of anelectroretinography device configured in accordance with the presenttechnology.

FIG. 5 is a cross sectional view through another embodiment of anelectroretinography device configured in accordance with the presenttechnology.

FIG. 6 is a cross sectional view through another embodiment of anelectroretinography device configured in accordance with the presenttechnology.

FIG. 7 is a cross sectional view through another embodiment of anelectroretinography device configured in accordance with the presenttechnology.

FIG. 8 is a cross sectional view through another embodiment of anelectroretinography device configured in accordance with the presenttechnology.

FIG. 9 is a cross sectional view through another embodiment of anelectroretinography device configured in accordance with the presenttechnology.

FIG. 10 is a cross sectional view through another embodiment of anelectroretinography device configured in accordance with the presenttechnology and positioned in contact with the anterior surface of asubject's eye.

FIG. 11 is a cross sectional view through another embodiment of anelectroretinography device configured in accordance with the presenttechnology.

FIG. 12 is a cross sectional view through another embodiment of anelectroretinography device configured in accordance with the presenttechnology.

FIG. 13 is a cross sectional view through another embodiment of anelectroretinography device configured in accordance with the presenttechnology.

FIG. 14 is a cross sectional view through another embodiment of anelectroretinography device configured in accordance with the presenttechnology.

FIG. 15 is a cross sectional view through another embodiment of anelectroretinography device configured in accordance with the presenttechnology.

FIG. 16 is a perspective view of another embodiment of anelectroretinography device configured in accordance with the presenttechnology as viewed from above the distal surface.

FIG. 17 is a cross sectional view through another embodiment of anelectroretinography device configured in accordance with the presenttechnology.

These and other embodiments of the present technology are described infurther detail below.

DETAILED DESCRIPTION

The present disclosure generally provides electroretinography devicesconfigured to detect a biopotential signal from an eye of a subject or aportion thereof (e.g., the retina) and transmit same to a processor. Insome embodiments, the electroretinography device includes an ocularportion including a conductive element and a signal relay operativelyconnecting the conductive element and a signal processor.

A person of ordinary skill in the art will understand that embodimentsof the present technology can have components and/or procedures inaddition to those shown or described herein, and that these and otherembodiments can be without several of the components and/or proceduresshown or described herein without deviating from the present technology.The headings provided herein are for convenience only.

For ease of reference, throughout this disclosure identical referencenumbers are used to identify similar or analogous components orfeatures, but the use of the same reference number does not imply thatthe parts should be construed to be identical. Indeed, in many examplesdescribed herein, the identically-numbered parts are distinct instructure and/or function.

Generally, unless the context indicates otherwise, the terms “distal”and “proximal” within this disclosure reference a position or directionwith respect to a subject's eye. “Distal” or “distally” therefore referto a position distant from or in a direction away from the subject'seye, while the terms “proximal” and “proximally” refer to a positionnear or in a direction toward the subject's eye.

Unless the context clearly requires otherwise, throughout thedescription and the claims, the words ‘comprise’, ‘comprising’, and thelike are to be construed in an inclusive sense as opposed to anexclusive or exhaustive sense; that is to say, in the sense of“including, but not limited to.” Words using the singular or pluralnumber also include the plural and singular number, respectively.Additionally, the words “herein,” “above,” and “below” and words ofsimilar import, when used in this application, shall refer to thisapplication as a whole and not to any particular portions of theapplication.

The description of embodiments of the disclosure is not intended to beexhaustive or to limit the disclosure to the precise form disclosed.While the specific embodiments of, and examples for, the disclosure aredescribed herein for illustrative purposes, various equivalentmodifications are possible within the scope of the disclosure, as thoseskilled in the relevant art will recognize.

Specific elements of any foregoing embodiments can be combined orsubstituted for elements in other embodiments. Furthermore, whileadvantages associated with certain embodiments of the disclosure havebeen described in the context of these embodiments, other embodimentsmay also exhibit such advantages, and not all embodiments neednecessarily exhibit such advantages to fall within the scope of thedisclosure.

Referring now to FIG. 1A, an electroretinography device 10 configuredaccording to one embodiment of the present disclosure comprises anocular portion 20 configured to be placed in contact with an anteriorsurface of a subject's eye, a conductive element 38 retained at leastpartially within the ocular portion 20, and a signal relay 30 configuredto transmit an electrical signal from the conductive element 38 to aprocessor (not shown). In some embodiments, the signal relay 30 includesone or more wires 34 operatively connected to the conductive element 38,for example by a flexible shield 32. The signal relay 30 is configuredto operatively connect to a signal processor (not shown), and thereforethe signal relay 30 may include any suitable connector 36 compatiblewith the signal processor to be used.

Referring now to FIGS. 1A and 1B collectively, the ocular portion 20includes a proximal portion 24 shaped to conform to the anterior surfaceof the subject's eye, including the cornea and/or the sclera. Forexample, the proximal surface 28 may include a curved shape, such as aconcave shape, that substantially conforms to the anterior surface of asubject's eye. The ocular portion 20 may also include a distal portion23 including one or more side walls 22. In some embodiments, the sidewall(s) 22 are configured to stop one or more eyelids from sliding overthe ocular portion 20 when in position on the anterior surface of thesubject's eye. In some embodiments, the distal portion 23 includes asingle side wall 22, and thus comprises a continuously curvedcross-sectional profile, such as a circular cross-sectional profile, anoval cross-sectional profile, an ellipsoid cross-sectional profile, orany other rounded cross-sectional profile. In other embodiments, thedistal portion has a polygonal cross-sectional profile, such as atriangular cross-sectional profile, a quadrilateral cross-sectionalprofile, a pentagonal cross-sectional profile, a hexagonalcross-sectional profile, a heptagonal cross-sectional profile, anoctagonal cross-sectional profile, a nonagonal cross-sectional profile,a decagonal cross-sectional profile, or any other polygonalcross-sectional profile. In some embodiments, the distal portion 23includes a cross-sectional profile including more than one curvedsegment and more than one straight segment.

Referring to FIG. 1A specifically, in some embodiments the ocularportion 20 may include a void 26 a (e.g., a gap, hole, passage, channel,etc.) extending through the ocular portion 20 to allow incident light topass through the ocular portion 20. The void 26 a may be incorporatedbefore, during or after formation of the ocular portion 20. For example,in some embodiments the void 26 a is formed in the ocular portion 20 aspart of a molding step. In other embodiments, the void 26 a is formed inthe ocular portion 20 after a molding step, for example by drilling ormilling the void 26 a into a molded ocular portion 20. In otherembodiments, such as that shown in FIG. 1B for example, the ocularportion 20 may include a distal portion 23 that does not include a void.In such embodiments, the distal portion 23 may include a distal surface26 having any suitable shape (e.g., contour), such as flat orsubstantially flat.

The proximal portion 28 may include one or two distinct contours toenable the ocular portion 20 to securely contact the anterior surface ofthe subject's eye. In some embodiments, the proximal portion 28 includesa single contour, for example that is complementary or substantiallycomplementary to the curvature of at least a portion of the cornea. Inother embodiments, such as that shown in FIG. 1B for example, theproximal portion 28 may include a first proximal surface 28 a having acurvature that is complementary or substantially complementary to thecurvature of at least a portion of the cornea, and a second proximalsurface 28 b having a curvature that is complementary or substantiallycomplementary to the curvature of at least a portion of the sclera.

The ocular portion 20 may be formed of any suitable material that isbiocompatible and transparent or translucent. In some embodiments, thematerial is flexible to reduce (e.g., minimize) the risk of mechanicalabrasion to the anterior surface of the eye and/or the eyelids when thedevice is positioned on the subject's eye. In some embodiments, thematerial has a Young's modulus of elasticity of no more than about 50mega-Pascals (50 MPa). In some embodiments, the materials comprise acomponent commonly used in the manufacture of soft contact lenses. Insome embodiments, the material comprises, consists essentially of, orconsists of polydimethylsiloxane (“PDMS”), which has a Young's modulusof elasticity of about 0.05 MPa to about 4.0 MPa.

The ocular portion 20 may be formed by any suitable fabricationtechniques depending on the type of material(s) selected for the ocularportion 20. For example, the ocular portion 20 may be molded (e.g.,injection molded) when the ocular portion 20 is formed predominantly ofPDMS.

The conductive element 38 includes one or more wires configured todetect a biopotential signal from the subject's eye, for example fromthe retina. Any suitable electrically conductive material may be used toform the conductive element 38. For example and without limitation, theconductive element 38 may comprise, consist essentially of, or consistof stainless steel, gold, platinum, a conductive hydrogel, a conductivepolymer, a conductive silicone, a doped silicon, a conductive saline, orcombinations thereof. The conductive element 38 is housed at leastpartially in the ocular portion 20. For example, the conductive element38 can be included at least partially within the distal portion 23, atleast partially within the proximal portion 24, or at least partially inboth, so long as the conductive element 38 is in electrical connectivitywith the biopotential signals produced by the subject's eye.

The conductive element 38 can be configured to form any suitable shape,such as a curved shape or a polygon. In some embodiments, the conductiveelement 38 forms a shape such as a loop (e.g., a discontinuous loop suchas that shown in FIG. 16 ). The conductive element 38 can beincorporated into the device 10 before, during or after formation of theocular portion 20. For example, in some embodiments the conductiveelement 38 is placed into a mold before the material used to form theocular portion is added to the mold. In other embodiments, theconductive element 38 is added to the ocular portion 20 after a moldingstep.

As shown in FIG. 2 , one embodiment of the ocular portion 20 includes adistal surface 26, at least one side wall 22, and a proximal surface 28which is curved to conform to the corneal surface of the subject's eye.The conductive element 38 is positioned within the ocular portion 20such that the conductive element 38 is at least partially exposedthrough the proximal surface 28.

In some embodiments, such as that shown in FIG. 3 , the ocular portion20 includes a distal surface 26, at least one sidewall 22, a conductiveelement 38, a first proximal surface 28 a configured to conform to thecornea of a subject's eye, and a second proximal surface 28 b configuredto conform to the sclera of the subject's eye. The conductive elementmay be positioned at any suitable location of the ocular portion 20. Asshown in FIG. 3 , for example, the conductive element is positionedwithin the ocular portion 20 such that the conductive element 38 is atleast partially exposed through the first proximal surface 28 a (e.g.,positioned to directly or indirectly contact the cornea). In otherembodiments, the conductive element 38 may be positioned such that it isat least partially exposed through the second proximal surface (e.g.,positioned to directly or indirectly contact the sclera, such as shownin FIG. 4 ).

In embodiments wherein the ocular portion 20 includes only oneconductive element, a second conductive element separate from theelectroretinography device 10 is typically attached to a portion of thesubject's body to serve as a reference electrode. However, in otherembodiments, the ocular portion 20 includes a first conductive electrodeconfigured to detect biopotential signals from a subject's eye and asecond conductive element configured to contact a different portion ofthe subject's eye. As shown in FIG. 4 , one such embodiment of an ocularportion 20 includes a distal surface 26, at least one side wall 22, afirst proximal surface 28 a configured to conform to a cornea of an eye,a second proximal surface 28 b configured to conform to a sclera of theeye, a first conductive element 38 and a second conductive element 39.The first conductive element 38 is positioned within the ocular portion20 such that at least a portion of the first conductive element 38 isexposed through the first proximal surface 28 a (e.g., positioned todirectly or indirectly contact the cornea). The second conductiveelement 39 is positioned within the ocular portion 20 such that at leasta portion of the second conductive element 39 is exposed through thesecond proximal surface 28 b (positioned to directly or indirectlycontact the sclera). In one embodiment, the first conductive element 38serves as the recording electrode (e.g., is configured to detectbiopotential signals from the eye), while the second conductive element39 serves as a reference electrode. In another embodiment, the firstconductive element 38 serves as the reference electrode, while thesecond conductive element 39 serves as the recording electrode (e.g., isconfigured to detect biopotential signals from the eye).

In some embodiments, the ocular portion 20 may include a secondconductive element positioned to contact a portion of the subject thatis not a portion of the anterior surface of the eye, such as one or botheyelids. For example, as shown in FIG. 6 , in some embodiments thedistal portion 23 includes a second conductive element 37 positionedsuch that at least a portion of the second conductive element 37 isexposed through the at least one side wall 22. In such embodiments, thefirst conductive element 38 may be positioned in any suitable locationto make direct or indirect contact with the anterior surface of the eye.For example, as shown in FIG. 6 , the first conductive element 38 may bepositioned within the ocular portion 20 such that a portion of the firstconductive element is exposed through the first proximal surface (e.g.,positioned to directly or indirectly contact the cornea). In otherembodiments, the first conductive element 38 is positioned within theproximal portion 24 such that at least a portion of the first conductiveelement 38 is exposed through the second proximal surface 28 b (e.g.,positioned to directly or indirectly contact the sclera).

In some embodiments, the proximal portion 24 is configured to allow oneor both eyelids to slide over the proximal portion 24. As shown in FIG.5 , for example, the proximal portion 24 may include a flange-like shapethat extends outwardly from the distal portion 23. In such embodiments,the conductive element 38 can be positioned in any suitable location asdescribed herein, including in a position such that at least a portionof the conductive element 38 is exposed through the first proximalsurface 28 a as shown in FIG. 5 .

In some embodiments, the ocular portion 20 is configured to permitincident light to reach the anterior surface of the eye unimpeded (e.g.,without first passing through any portion of the ocular portion 20). Insuch embodiments, the ocular portion 20 may include a void 26 aextending through the ocular portion 20. In some embodiments, such asthat shown in FIG. 7 , the ocular portion 20 may include a distalportion 23 which includes a void 26 a extending through the distalportion 23 and the proximal portion 24 (including through the firstproximal surface 28 a). In such embodiments, the distal surface 26 mayinclude a contour 26 b (e.g., a bevel or curve) adjacent to the void 26a. The first conductive element 38 can be positioned in any suitablelocation as described herein, including in a position such that at leasta portion of the conductive element 38 is exposed through the firstproximal surface 28 a as shown in FIG. 7 .

Referring to FIGS. 8, 9 and 11 collectively, some embodiments,particularly those including a void 26 a through the ocular portion 20,include an ocular portion 20 that additionally includes a stabilizingelement 40. The stabilizing element 40 comprises, consists essentiallyof, or consists of a material that is more rigid than the material usedto form the remainder of the ocular portion 20. In such embodiments, thestabilizing element provides increased mechanical rigidity to the ocularportion 20, for example to resist lateral forces (e.g., pressure exertedon the side wall(s) 22 by the subject's eyelids). In some embodiments,the stabilizing element 40 comprises, consists essentially of, orconsists of a material having a Young's modulus of elasticity of 100 MPaor greater. In some embodiments, the stabilizing element 40 comprises,consists essentially of, or consists of a tetrafluoroethylene (e.g.,TEFLON), an acetal resin (e.g., DELRIN), an acrylic (e.g., poly(methylmethacrylate)), a polycarbonate, a glass, stainless steel, or acombination thereof. The size and amount of the stabilizing element 40to be used depends in part on the relative difference in Young's modulusvalues of the stabilizing element 40 and the material comprising theocular portion 20, and in part on the shape of the ocular portion 20. Ingeneral, however, less stabilizing element 40 is required when thedifference in Young's modulus values is large and when the ocularportion 20 does not include voids or other discontinuities (e.g., void26 a). The stabilizing element 40 can be introduced into the devicebefore, during or after formation of the ocular portion 20. For example,in some embodiments the stabilizing element 40 is placed into a moldbefore the material used to form the ocular portion is added to themold. In other embodiments, the stabilizing element is added to theocular portion 20 after a molding step.

The stabilizing element 40 may be positioned at any suitable locationwithin the ocular portion 20, and may be configured in any suitableshape to provide rigidity to the ocular portion 20. In some embodiments,the stabilizing element 40 has a general ring shape and is positionedinside the distal portion 23 of the ocular portion 20, such as shown inFIGS. 8-9 . In other embodiments, the stabilizing element 40 is at leastpartially exposed. For example, as shown in FIG. 11 , the stabilizingelement 40 may be configured as a ring positioned around the one or moreside walls 22 of the ocular portion 20. In such embodiments, thestabilizing element 40 may be positioned at or near the distal surface26, as shown in FIG. 11 , or alternatively the stabilizing element maybe positioned such that at least a portion of the stabilizing element 40is covered by the distal surface 26.

Referring now to FIG. 8 , one embodiment of the ocular portion 20 of thepresent technology includes a distal portion 23 having at least one sidewall 22, a distal surface 26, a void 26 a, and a stabilizing element 40within the distal portion 23. The ocular portion 20 further includes aconductive element 38 positioned at or near the first proximal surface28 a and the second proximal surface 28 b. The stabilizing element 40 inthis embodiment is generally configured as a rounded shape (e.g., aring) that extends through all or substantially all of the ocularportion 20.

As shown in FIG. 9 , another embodiment of the ocular portion 20includes a conductive element 38 positioned at or near a first proximalsurface 28 a and/or a second proximal portion 28 b, and a distal portion23 having at least one side wall 22, a stabilizing element 40, and adistal surface 26 that is generally convex in shape. The stabilizingelement 40 in such embodiments may be relatively larger and/or formed ofa material having a relatively higher Young's modulus value than, forexample, the stabilizing element 40 used in embodiments such as thatshown in FIG. 8 .

Referring now to FIG. 11 , another embodiment of the ocular portion 20includes a conductive element 38 positioned within one or more channels27 formed within the proximal surface 28, a distal surface 26, and astabilizing element 40 positioned at or near the outer edge of the sidewall 22. The stabilizing element 40 may be configured to be flush withthe distal surface 26, or alternatively may be configured to be coveredat least partially by the distal surface 26.

As shown in FIG. 12 , in some embodiments the one or more side walls 22have a contoured surface that accommodates the subject's eyelids. Insuch embodiments, the contoured surface may be generally concave and theside wall(s) 22 may have a height sufficient to prevent the eyelids fromclosing over the distal surface 26.

Referring now to FIG. 13 , an ocular portion 20 of some embodiments ofthe present technology includes a distal surface 26 having a generallyconcave shape. In such embodiments, the ocular portion 20 additionallyserves as a diverging lens to affect the distribution of incident lighton the subject's retina. This configuration of the distal surface 26 maybe used in conjunction with any other embodiment of the presenttechnology; for example the proximal portion 24 may be configured toinclude a flange shape, and may include a conductive element 38 at ornear a first proximal surface 28 a configured to conform to thesubject's cornea and/or a second proximal surface 28 b configured toconform to the subject's sclera. The one or more side walls 22 may beconfigured to be generally straight as shown in FIG. 13 , or mayalternatively adopt another shape, such as generally concave as shown inFIG. 12 .

As shown in FIG. 14 , another embodiment of the present technologyprovides an ocular portion 20 including a lens 50 configured, forexample, to affect the subject's acuity in any desired manner. Thedistal surface 26 in such embodiments may include one or more retainingportions 25 configured to securely retain the lens 50. In someembodiments, the retaining portions 25 are configured to enable exchangeor replacement of the lens 50 before or after the ocular portion 20 isinstalled on an anterior surface of the subject's eye. For example, theretaining portions 25 may be configured to be sufficiently flexible toallow a clinician to remove the lens 50 from the ocular portion 20without exerting undue pressure or lateral force on the ocular portion20.

In some embodiments, the ocular portion 20 further includes a diffusingcomponent which has an index of refraction different than the index ofrefraction of the flexible material used to form the ocular portion 20.As shown in FIG. 15 , the diffusing component 60 may be dispersed evenlyor substantially evenly throughout the ocular portion 20. In suchembodiments, incident light L enters the ocular portion 20 through thedistal surface 26 and is scattered by passing through the two materialssuch that the emerging light L′ is scattered (e.g., diffuse). Thediffusing component 60 may be incorporated into any embodiment disclosedherein. As such, the conductive element 38 may be located at anysuitable location including, for example, at or near the proximalsurface 28 as shown in FIG. 15 .

As shown in FIG. 16 , the conductive element 38 is operatively connected(e.g., electrically connected) to the signal relay 30, and may beprotected from breakage or damage by the flexible portion 32 of thesignal relay 30. The conductive element 38 may adopt a loop or partialloop shape, as shown in FIG. 16 . In such embodiments, the conductiveelement 38 is positioned near the side wall 22 and below the distalsurface 26. The proximal portion 24 extends beyond the edge of the sidewall 22 to allow the subject's eye lids to slide over the proximalportion 24 and thus apply a stabilizing force to the ocular portion 20.

Referring now to FIG. 17 , an ocular portion 20 of the presenttechnology is formed of a material comprising, consisting essentiallyof, or consisting of a component having a Young's modulus of no morethan about 50 MPa (e.g., PDMS), and includes a conductive element 38, adistal portion 23 and a proximal portion 24. The proximal portion 24includes a first proximal surface 28 a configured to conform to thecornea of a subject's eye, and a second proximal surface 28 b configuredto conform to the sclera of the subject's eye. The proximal portion 28includes a flange shaped extension configured to enable the subject'seyelids to slide over the flange. The conductive element 38 is formed ofa conductive material as described herein, and is positioned within achannel 27 formed in the proximal surface 28 a/28 b which enables theconductive element 38 to be in indirect contact with the anteriorsurface of the subject's eye. In such an embodiment, the biopotentialsignal is transmitted to the conductive element 38 through a conductivemedium between the anterior surface of the eye and the conductiveelement 38, such as saline, natural tears, artificial tears, or asimilar biocompatible and electrically conductive fluid. The distalportion 23 includes a side wall 22 that is generally perpendicular tothe distal surface 26. A diffusing component 60 is positioned adjacentto the distal surface 26 and is configured to diffuse incident light.The diffusing component 60 may include a translucent material, such as alight-scattering component suspended in PDMS or another suitablesubstrate, that permits diffuse light to pass through the ocular portion20 to the subject's eye. The diffusing component 60 may be applied as acoating to the distal surface 26 after formation of the remainder of thedistal portion 23, or may be formed integrally with the ocular portion20 along with the remainder of the distal portion 23.

Referring now to FIG. 10 , an ocular portion 20 consistent with thepresent technology is positioned on the anterior surface of a subject'seye E. In some embodiments, the ocular device 20 is positioned such thata first distal surface 28 a conforms to and contacts the cornea 1007,while a second proximal surface 28 b conforms to and contacts the sclera1008. The upper eyelid 1005 and lower eyelid 1006 help retain the ocularportion 20 against the cornea 1007 and the sclera 1008 by, for example,applying pressure against the flange-shaped portion of the distalportion 24. In such a configuration, the distal surface 26 is generallytangential to the cornea 1007, such that incident light can pass throughthe ocular portion 20 through the pupil 1010 and lens 1009 to the retinaR. Biopotential signals produced by the illuminated retina R are thendetectable by the conductive element 38, which is positioned in director indirect contact with the anterior surface of the eye E.

This disclosure is not intended to be exhaustive or to limit the presenttechnology to the precise forms disclosed herein. Although specificembodiments are disclosed herein for illustrative purposes, variousequivalent modifications are possible without deviating from the presenttechnology, as those of ordinary skill in the relevant art willrecognize. In some cases, well-known structures and functions have notbeen shown or described in detail to avoid unnecessarily obscuring thedescription of the embodiments of the present technology. Although stepsof methods may be presented herein in a particular order, alternativeembodiments may perform the steps in a different order. Similarly,certain aspects of the present technology disclosed in the context ofparticular embodiments can be combined or eliminated in otherembodiments. While advantages associated with certain embodiments of thepresent technology may have been disclosed in the context of thoseembodiments, other embodiments can also exhibit such advantages, and notall embodiments need necessarily exhibit such advantages or otheradvantages disclosed herein to fall within the scope of the presenttechnology. Accordingly, this disclosure and associated technology canencompass other embodiments not expressly shown or described herein.

I/We claim:
 1. An ocular device configured to detect one or morebiopotential signals from a patient, the ocular device comprising: anocular region configured to be placed in contact with an anteriorsurface of an eye, wherein the ocular region is monolithic andcomprises— a distal portion including an outermost sidewall and adistalmost edge defining a plane extending laterally across the ocularregion; a distal surface extending across at least a portion of theocular region, wherein the distal surface is proximal to the planedefined by the distalmost edge; and a proximal portion coupled to thedistal portion and including a flange region extending from the sidewallof the distal portion in a radially outward direction, the flange regionincluding an outer surface configured to abut an eyelid of the patientwhen the device is disposed over the eye; and a conductor disposedwithin the ocular region and configured to be operatively connected to asignal relay.
 2. The ocular device of claim 1, wherein the distalsurface is convex and extends between outer regions of the ocularregion.
 3. The ocular device of claim 1, wherein the distal portion hasa first maximum cross-sectional dimension and the proximal portion has asecond maximum cross-sectional dimension greater than the first maximumcross-sectional dimension.
 4. The ocular device of claim 1, wherein,when the device is disposed over the eye, the distal portion isconfigured to inhibit the eyelid from blocking light received by theeye.
 5. The ocular device of claim 1, wherein the proximal portioncomprises an inner surface having a first region with a first curvature,and a second region radially outward of the first region and having asecond curvature different than the first curvature.
 6. The oculardevice of claim 1, wherein the conductor is disposed within the ocularregion such that a portion of the conductor is exposed, and wherein,when the device is disposed over the eye, the conductor is spaced apartfrom the anterior surface of the eye.
 7. The ocular device of claim 1,wherein the conductor consists of a conductive element forming an openor closed loop.
 8. The ocular device of claim 1, wherein the flangeregion extends from the sidewall of the distal portion such that across-sectional dimension of the flange region within the proximalportion decreases in a distal direction.
 9. An electroretinographydevice, comprising: an ocular region comprising— a first portionincluding an outermost sidewall and a distalmost surface defining aplane; a second portion positioned radially inward of the sidewall andextending across the ocular region, the second portion including agenerally convex distal surface that is proximal to the plane defined bythe first portion; and a third portion proximal to the first portion andthe second portion, the third portion including a flange regionextending from the sidewall of the first portion in a radially outwarddirection, the flange region including an inner surface and an outersurface each of which is curved such that, when the device is disposedover the eye, the outer surface abuts an eyelid of the eye and the innersurface abuts a sclera of the eye; and a conductor disposed within theocular region and configured to be operatively connected to a signalrelay.
 10. The electroretinography device of claim 9, wherein, when thedevice is disposed over the eye, only a portion of the conductor, facingat least partially toward the eye, is exposed through the ocular region.11. The electroretinography device of claim 9, wherein the conductor isa single conductive element forming an open or closed loop.
 12. Theelectroretinography device of claim 9, wherein, when the device isdisposed over the eye, the conductor is spaced apart from the anteriorsurface of the eye.
 13. The electroretinography device of claim 9,wherein the inner surface of the flange region includes a portionconfigured to conform to and contact a sclera of the eye when the deviceis disposed over the eye.
 14. The electroretinography device of claim 9,wherein the inner and outer surfaces of the flange region have a firstthickness, and wherein the first portion has a second thickness greaterthan the first thickness.
 15. The electroretinography device of claim 9,wherein the flange region extends partially distally in a radiallyoutward direction.
 16. The electroretinography device of claim 9,further comprising a stabilizing element disposed within the ocularregion, wherein the single material of the ocular region is a firstmaterial having a first rigidity and the stabilizing element is formedof a second material having a second rigidity greater than the firstrigidity.
 17. The electroretinography device of claim 9, wherein theocular region is formed of a single material and comprises a continuoussurface extending along an entirety of the ocular region.
 18. Theelectroretinography device of claim 9, wherein when the device isdisposed over the eye, the ocular region covers an entire anteriorsurface of the eye and holds open the eyelid of the patient.
 19. Theelectroretinography device of claim 18, wherein the ocular region isformed of a single material and comprises a continuous surface extendingalong an entirety of the ocular region.
 20. The electroretinographydevice of claim 9, wherein the first portion has a first maximumcross-sectional dimension and the third portion has a second maximumcross-sectional dimension greater than the first maximum cross-sectionaldimension.
 21. The electroretinography device of claim 9, wherein theinner surface comprises a first region having a first curvature and asecond region, radially outward of the first region, having a secondcurvature different than the first curvature.
 22. Theelectroretinography device of claim 21, wherein the second curvature hasa larger radius of curvature than that of the first curvature.
 23. Anelectroretinography device, comprising: a first portion including anoutermost sidewall and a distalmost surface defining a plane; a secondportion positioned radially inward of the sidewall and extending acrossthe ocular region, the second portion including a convex distal surfacethat is proximal to the plane defined by the first portion; and a thirdportion proximal to the first portion and including a flange regionextending from the sidewall of the first portion in a radially outwarddirection, the flange region including inner and outer surfaces each ofwhich is curved such that, when the device is disposed over the eye, theouter surface abuts an eyelid of the eye and the inner surface covers ananterior surface of the eye, wherein the first portion, the secondportion, and the third portion are formed of a single material.